So my late 2012 Mini is compatible. But I'm still running Yosemite... No real software restrictions... I'm ashamed to admit I haven't used it for a month or more.But I've got stuff to do that means I will be on it more. Mostly web based (Chrome) and whatnot. So I figure I should upgrade the OS.

There are going to be a lot of things that aren't perfect out of the gate with APFS - I'd personally wait until a compelling need - some kind of benefit was to be attained before going to 10.13. That said, I'd probably not hesitate at this time to jump up to 10.12 now vs. 10.13 if you are any to update to something more current.

I read that Office won't work. Unfortunately, I must have it for academic work, 100% Word compatibility. I'll wait a while.

That old man - he don't think like no old man...
Now I wouldn't want to be within 400 - 500 yards of one of them nuclear bombs when it goes off! WW1 Vet Old Man
"He's pinned under an outcropping of rock. Lucky for him, the rock kept the dirt from burying him alive."
If idiots could fly, this place would be an airport. And I'd be a TSA agent.
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will you be synching all your other devices and are they all also up to date ?

The Phorum Wall keeps us safe from illegal characters and words
The doorstep to the temple of wisdom is the knowledge of one's own ignorance. -Benjamin Franklin
BOYCOTT YOPLAIT [www.noyoplait.com]
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Also, you won't be automatically "upgraded" to new file system unless your boot drive is an SSD. IIRC you can still revert to the current file system using High Sierra's Disk Utility. Can anyone confirm or clarify.